Abstract: An axial-flow fan structure is disclosed, having a localized area expansion between the rotor (i.e. front rotating impeller) and stator blades (i.e. rear stationary or fixed blades, sometimes called de-swirl vanes). The area expansion is provided by utilizing an impeller having a (slightly) falling tip contour (FTC).

Abstract: In accordance with at least some embodiments, a computer system includes an enclosure (202) configured to hold at least one resource unit (204). The computer system also comprises a plurality of mixed-flow ducted fans units (400) selectively attached to the enclosure (202). Each mixed-flow ducted fan unit (400) comprises a duct (102) having an intake diameter, a bellmouth diameter, and an exhaust diameter. The bellmouth diameter is less than the intake diameter and the exhaust diameter.

Abstract: A cooling fan having motor and an impeller. The cooling fan may comprise a three-phase DC motor. The impeller may comprise a hub to house the three-phase DC motor and a plurality of blades extending from the hub. Each blade may have a height that is at least 25 % of the impeller diameter.

Abstract: In accordance with at least some embodiments, a computer system includes an enclosure (202) configured to hold at least one resource unit (204). The computer system also comprises a plurality of mixed-flow ducted fans units (400) selectively attached to the enclosure (202). Each mixed-flow ducted fan unit (400) comprises a duct (102) having an intake diameter, a bellmouth diameter, and an exhaust diameter. The bellmouth diameter is less than the intake diameter and the exhaust diameter.

Abstract: Disclosed is a compact and integrated fan, pump, and heat exchanger system where air-cooling is performed via the fan, liquid cooling is performed via a pump, and heat exchange fins in thermal contact with a fluid channel act as a heat exchanger. Heated fluid is carried inside the fluid channel, where heat therein is conducted to the fins. The air flows around the outside surfaces of the fins so that the heat transfers from the heated fluid into the air stream.

Abstract: According to embodiments of the invention, an impeller includes a hub, and a plurality of radial blades for drawing the air inflow axially through the hub and delivering the drawn air radially towards the outside. A ring is attached to one or more tips of the plurality of radial blades to block a portion of the tip toward the inlet side of the impeller. The preferred blockage factor, which is the ratio of a height of the ring to a height of the tip, is approximately in a range between 30% and 40%. By blocking a portion of the tip toward the inlet side of the impeller, the low-momentum flow zone toward the inlet side of impeller is blocked, while the high-momentum flow zone toward the back side of impeller is enhanced. As such, the performance of the impeller is enhanced.

Abstract: An axial-flow fan structure is disclosed, having a localized area expansion between the rotor (i.e. front rotating impeller) and stator blades (i.e. rear stationary or fixed blades, sometimes called de-swirl vanes). The area expansion is provided by utilizing an impeller having a (slightly) falling tip contour (FTC).

Abstract: An impeller blade hub profile which inhibits stall is described. In an embodiment, the hub profile includes a frontal rising contour followed by a rear constant contour. In another embodiment, the hub profile includes a frontal rapidly rising contour followed by a substantially rear constant contour. It was discovered that this combination is much more effective than conventionally known profiles. Also, the present invention provides a unique way of turning the flow within the passages of the rotating impeller blades. In an embodiment, the blade does not turn much over either the front portion of the hub or the rear portion of the hub, but instead turns near the boundary between the front portion and the rear portion.

Abstract: A fan housing is provided with slots formed in the enclosure of the fan housing. The slots are sized appropriately to filter the noise generated during operation of the cooling fan; e.g., tonal noise produced by the rotation of the blades. The slots may either be vented to the outside of the enclosure or closed off.

Abstract: A fan apparatus includes a ducted housing with an axis of rotation including a first section and a second section. The fan apparatus further includes a first plurality of vanes being radially coupled within the first section and a second plurality of vanes being radially coupled within the second section. Additionally, the fan apparatus includes an impeller with a plurality of blades rotatably disposed within the ducted housing between the first plurality of vanes and the second plurality of vanes for rotary motion about the axis of rotation. The first plurality of vanes are stationary in a first arrangement to guide an inflow of air towards the impeller. The plurality of blades are rotary in a second arrangement to have a rotational direction substantially opposite to the inflow of air guided by the first arrangement. The second plurality of vanes are stationary in a third arrangement to diffuse an outflow of air substantially along the axis of rotation.

Abstract: An apparatus for air cooling an object. The apparatus includes a plate including a first surface and a second surface and a plurality of aerodynamic fins being fixedly disposed on the first surface in an arrangement along periphery of the plate. The arrangement of the plurality of aerodynamic fins defining a central volume of space. Additionally, the apparatus includes a blower including a plurality of impeller blades rotatably disposed within the central volume of space for rotary motion about an axis of rotation. In particular, the second surface is for thermally contacting with the object and the axis of rotation is substantially perpendicular to the first surface. Furthermore, the rotary motion of the blower creates an air inflow along the axis of rotation into the central volume of space and an air outflow through the plurality of aerodynamic fins in radial directions.

Abstract: According to embodiments of the invention, an impeller includes a hub, and a plurality of radial blades for drawing the air inflow axially through the hub and delivering the drawn air radially towards the outside. A ring is attached to one or more tips of the plurality of radial blades to block a portion of the tip toward the inlet side of the impeller. The preferred blockage factor, which is the ratio of a height of the ring to a height of the tip, is approximately in a range between 30% and 40%. By blocking a portion of the tip toward the inlet side of the impeller, the low-momentum flow zone toward the inlet side of impeller is blocked, while the high-momentum flow zone toward the back side of impeller is enhanced. As such, the performance of the impeller is enhanced.

Abstract: A fan impeller includes rotating ring attached to the tip of dual-swept fan blades. Besides shrouding the impeller; the blades are dual-swept forward, and sweep increases in magnitude towards the tip. The shrouded dual-swept impeller resides inside classical fan housing. The integrated effects of shrouding the impeller, forward sweep into the direction of incoming flow, and forward sweep into the direction of rotation (circumferential forward sweep) render the fan quiet; the magnitude of noise reduction is between 7 and 12 dB.

Abstract: A fan blade is described having a substantially non-varying stagger angle along its radial length. In one embodiment, a fan blade has a substantially non-varying stagger angle and a substantially non-varying camber angle along its radial length. In another embodiment, each airfoil section of the blade has at least substantially the same stagger angle or substantially the same camber angle.

Abstract: A cooling fan is disclosed. The cooling fan comprises fan blades having a primary blade component and a secondary blade component. The primary blade component produces an axial airflow. The secondary blades produce a radial airflow. The axial airflow and the radial airflow, respectively created by the primary blades and the secondary blades, combine to provide an increase axial outflow. The primary and secondary blades combine the axial and radial flows respectively created by the blades to produce an increased outflow. The design has been observed to reduce tonal noise as well.

Abstract: Disclosed is a hub of an axial fan. The hub includes primary fan blades and splitter blades disposed between pairs of the primary fan blades. The resulting hub has been observed to reduce tonal noise during fan operation.

Abstract: A fan comprises a hub and a stator coil disposed with the hub. A first set of blades is disposed about the hub. Second blades are disposed on an interior of the hub. An opening is provided through the face of the hub. When the fan is operating, a flow of air passes through the opening which is then captured by the second blades and redirected across the stator coils to provide cooling.